[PATCH 4/5] nouveau: add dynamic gpu power off support.

[Dave Airlie]

From: Dave Airlie <airlied at redhat.com>

This adds the interfaces for nouveau to dynamically power off
the GPU in an optimus system.

It's based on nouveau git so may not apply everywhere.

Signed-off-by: Dave Airlie <airlied at redhat.com
---
 drivers/gpu/drm/nouveau/nouveau_drm.c |  2 ++
 drivers/gpu/drm/nouveau/nouveau_drm.h |  3 ++
 drivers/gpu/drm/nouveau/nouveau_pm.c  | 57 +++++++++++++++++++++++++++++++++--
 drivers/gpu/drm/nouveau/nouveau_vga.c |  4 ++-
 4 files changed, 62 insertions(+), 4 deletions(-)

diff --git a/drivers/gpu/drm/nouveau/nouveau_drm.c b/drivers/gpu/drm/nouveau/nouveau_drm.c
index 9fb56b3..e7735a8 100644
--- a/drivers/gpu/drm/nouveau/nouveau_drm.c
+++ b/drivers/gpu/drm/nouveau/nouveau_drm.c
@@ -604,6 +604,8 @@ driver = {
 	.dumb_map_offset = nouveau_display_dumb_map_offset,
 	.dumb_destroy = nouveau_display_dumb_destroy,
 
+	.dynamic_off_check = nouveau_dynamic_power_check,
+	.dynamic_set_state = nouveau_dynamic_power_set_state,
 	.name = DRIVER_NAME,
 	.desc = DRIVER_DESC,
 #ifdef GIT_REVISION
diff --git a/drivers/gpu/drm/nouveau/nouveau_drm.h b/drivers/gpu/drm/nouveau/nouveau_drm.h
index ab0c174..f39f814 100644
--- a/drivers/gpu/drm/nouveau/nouveau_drm.h
+++ b/drivers/gpu/drm/nouveau/nouveau_drm.h
@@ -148,4 +148,7 @@ int nouveau_drm_resume(struct pci_dev *);
 		NV_PRINTK(KERN_DEBUG, "D", drm, fmt, ##args);                  \
 } while (0)
 
+bool nouveau_dynamic_power_check(struct drm_device *dev);
+int nouveau_dynamic_power_set_state(struct drm_device *dev, int state);
+
 #endif
diff --git a/drivers/gpu/drm/nouveau/nouveau_pm.c b/drivers/gpu/drm/nouveau/nouveau_pm.c
index 3c55ec2..fc132c3 100644
--- a/drivers/gpu/drm/nouveau/nouveau_pm.c
+++ b/drivers/gpu/drm/nouveau/nouveau_pm.c
@@ -28,12 +28,12 @@
 #include <linux/power_supply.h>
 #include <linux/hwmon.h>
 #include <linux/hwmon-sysfs.h>
-
+#include <linux/vga_switcheroo.h>
 #include "drmP.h"
-
+#include "drm_crtc_helper.h"
 #include "nouveau_drm.h"
 #include "nouveau_pm.h"
-
+#include "nouveau_acpi.h"
 #include <subdev/bios/gpio.h>
 #include <subdev/gpio.h>
 #include <subdev/timer.h>
@@ -962,6 +962,7 @@ nouveau_pm_init(struct drm_device *dev)
 	register_acpi_notifier(&pm->acpi_nb);
 #endif
 
+	drm_dynamic_power_init(dev);
 	return 0;
 }
 
@@ -1007,3 +1008,53 @@ nouveau_pm_resume(struct drm_device *dev)
 	nouveau_pm_perflvl_set(dev, perflvl);
 	nouveau_pwmfan_set(dev, pm->fan.percent);
 }
+
+/* rules for what we want
+   if we are an optimus laptop,
+   with no active crtc/encoders/connectors
+   with no channel activity for 4-5s
+*/
+
+bool nouveau_dynamic_power_check(struct drm_device *dev)
+{
+	struct nouveau_drm *drm = nouveau_drm(dev);
+	struct drm_crtc *crtc;
+
+	/* are we optimus enabled? */
+	if (!nouveau_is_optimus()) {
+		DRM_DEBUG_DRIVER("failing to power off - not optimus\n");
+		return false;
+	}
+
+	list_for_each_entry(crtc, &drm->dev->mode_config.crtc_list, head) {
+		if (crtc->enabled) {
+			DRM_DEBUG_DRIVER("failing to power off - crtc active\n");
+			return false;
+		}
+	}
+	return true;
+}
+
+int nouveau_dynamic_power_set_state(struct drm_device *dev, int state)
+{
+	struct nouveau_drm *drm = nouveau_drm(dev);
+	pm_message_t pmm = { .event = PM_EVENT_SUSPEND };
+
+	if (state == DRM_SWITCH_POWER_DYNAMIC_OFF) {
+		dev->switch_power_state = DRM_SWITCH_POWER_DYNAMIC_OFF;
+		drm_kms_helper_poll_disable(drm->dev);
+		vga_switcheroo_set_dynamic_switch(dev->pdev, VGA_SWITCHEROO_OFF, false);
+		nouveau_switcheroo_optimus_dsm();
+		nouveau_drm_suspend(drm->dev->pdev, pmm);
+		vga_switcheroo_set_dynamic_switch(dev->pdev, VGA_SWITCHEROO_OFF, true);
+	} else if (state == DRM_SWITCH_POWER_ON) {
+		vga_switcheroo_set_dynamic_switch(dev->pdev, VGA_SWITCHEROO_ON, true);
+		nouveau_drm_resume(dev->pdev);
+		vga_switcheroo_set_dynamic_switch(dev->pdev, VGA_SWITCHEROO_ON, false);
+		drm_kms_helper_poll_enable(dev);
+		dev->switch_power_state = DRM_SWITCH_POWER_ON;
+	}
+
+	return 0;
+}
+
diff --git a/drivers/gpu/drm/nouveau/nouveau_vga.c b/drivers/gpu/drm/nouveau/nouveau_vga.c
index 37fcc9d..539722f 100644
--- a/drivers/gpu/drm/nouveau/nouveau_vga.c
+++ b/drivers/gpu/drm/nouveau/nouveau_vga.c
@@ -33,6 +33,8 @@ nouveau_switcheroo_set_state(struct pci_dev *pdev,
 	struct drm_device *dev = pci_get_drvdata(pdev);
 	pm_message_t pmm = { .event = PM_EVENT_SUSPEND };
 
+	if (nouveau_is_optimus() && state == VGA_SWITCHEROO_OFF)
+		return;
 	if (state == VGA_SWITCHEROO_ON) {
 		printk(KERN_ERR "VGA switcheroo: switched nouveau on\n");
 		dev->switch_power_state = DRM_SWITCH_POWER_CHANGING;
@@ -80,7 +82,7 @@ nouveau_vga_init(struct nouveau_drm *drm)
 {
 	struct drm_device *dev = drm->dev;
 	vga_client_register(dev->pdev, dev, NULL, nouveau_vga_set_decode);
-	vga_switcheroo_register_client(dev->pdev, &nouveau_switcheroo_ops, false);
+	vga_switcheroo_register_client(dev->pdev, &nouveau_switcheroo_ops, nouveau_is_optimus());
 }
 
 void
-- 
1.7.12